Field of the Invention
The present invention relates to a heat exchanger with a thermal storage function and a method of manufacturing the heat exchanger.
Discussion of the Background
For example, in order to protect the environment and improve fuel consumption of automobiles, there has been proposed an automobile designed to automatically stop the engine when the automobile stops, for example, so as to wait for a traffic light to change.
However, an ordinary car air conditioner has a problem in that, when the engine of an automobile in which the air conditioner is mounted is stopped, a compressor driven by the engine stops, and supply of refrigerant (medium for conveying cool) to an evaporator stops, whereby the cooling capacity of the air conditioner sharply drops.
One conceivable measure for solving such a problem is imparting a cool storage function to the evaporator, to thereby enable cooling of a vehicle compartment by releasing the cool stored in the evaporator, when the compressor stops as a result of stoppage of the engine.
Such an evaporator with a cool storage function has been proposed (see Japanese Patent Application Laid-Open (kokai) No. 2011-12947). In the proposed evaporator, a plurality of flat refrigerant flow tubes (heat exchange tubes) are disposed in parallel such that they are spaced from one another. The evaporator has air-passing clearances each formed between refrigerant flow tubes located adjacent to each other. Cool storage material containers filled with a cool storage material are disposed in some air-passing clearances, and outer fins are disposed in the remaining air-passing clearances. Each cool storage material container is formed by brazing together peripheral edge portions of two metal plates, and a cool storage material is charged into a cool storage material accommodation space provided between the two metal plates.
Although not clearly shown in the above-mentioned publication, a cool storage material charging inlet is formed in each cool storage material container so as to charge the cool storage material into the cool storage material container. After the cool storage material is charged into the cool storage material accommodation space through the cool storage material charging inlet, the cool storage material charging inlet must be closed.
Incidentally, in the case of the evaporator with a cool storage function disclosed in the above-mentioned publication, a conceivable simple way of forming the cool storage material charging inlet on each cool storage material container is providing an outward projecting semi-cylindrical portion at the peripheral edge of each metal plate, providing outward flanges along opposite side edges of the semi-cylindrical portion of each metal plate, and joining together the corresponding outward flanges of the semi-cylindrical portions of the two metal plates. Also, a conceivable simple way of closing such a cool storage material charging inlet is press-fitting a cylindrical columnar plug into the cool storage material charging inlet after charging of the cool storage material.